Excel II: Ecuation solver

Hello again. The second big project we've made with excel is an ecuation solver which can solve simple ecuations of first degree and of second degree quickly.

In the first sheet there must be a front sheet that links to the rest of the sheets: 1st degree ecuation, representation of the 1st degree ecuation, 2nd degree ecuation and representation of the 2nd degree ecuation. You can do it with a macro or with a hyperlink as the image shows.

For the first degree ecuation I just had to write the ecuation leaving gaps where each term had to be written and leave a solution gap where I wrote the formula to solve the ecuation. I also made it notify if there were terms left. So my function was =SI(D7=0;SI(F7=0;"¡Faltan coeficientes en la ecuación!";"¡Faltan coeficientes en la ecuación!");(H7-F7)/D7). I solved the ecuation leaving the x alone.

For its representation I wrote the formula as in the previous sheet and gave several values for the x in a chart and, to obtain the respective value of y, I just made a formula replacing x by the value given respectively: =SI(C10=" ";" ";$D$5*C10+$F$5-$H$5). To add the graphic you insert a lines graphic and set the data as the image shows. I also added linking buttons as in all the sheets.

And for the second degree ecuation it's the same but with a different formula: =SI(D7=0;SI(F7=0;SI(H7=0;"¡Faltan coeficientes en la ecuación!";"Ecuación incompatible");"Ecuación de primer grado");SI((F7^2-4*D7*H7)>=0;((-F7+(RAIZ(F7^2-4*D7*H7)))/(2*D7));"Sin resultados reales")) for the first result and: =SI(D7=0;SI(F7=0;SI(H7=0;"¡Faltan coeficientes en la ecuación!";"Ecuación incompatible");"Sólo hay un resultado");SI((F7^2-4*D7*H7)>=0;((-F7-(RAIZ(F7^2-4*D7*H7)))/(2*D7));"Sin resultados reales")) for the second result. 

To make its representation it's the same, replace the x by different values to obtain the y, and create the graphic with that values. The formula I used was: =SI(C10="";"";$D$5*(C10^2)+$F$5*C10+$H$5). 

I made erase and print buttons with macros in each sheet so, if you want to know how I did them, visit my previous post. I also added linking buttons in each sheet to link to the rest of the sheets.

I hope it was useful and if you've any questions, please ask me. See you.